#include <bits/stdc++.h>

using namespace std;

class Solution {
public:
    int countEven(int num)
    {
	int res = 0;
	for (int i = 2; i <= num; ++i)
	    if (isEven(i))
		res++;
	return res;
    }

private:
    bool isEven(int num)
    {
	int res = 0;
	while (num > 0) {
	    res += num % 10;
	    num /= 10;
	}
	return !(res & 1);
    }
};

int main()
{
    [[maybe_unused]] Solution solution;
    return 0;
}
